The present invention relates to systems configured to reduce the impact of greenhouse gas emissions from natural gas or oil wells.
Oil and gas wells consist of a number of concentric casings, which extended into the ground to different depths. The casings include the production casing, which produces oil or natural gas for sale, and a surface casing vent near the top of the well. Whether due to material failure, high pressures, the integrity of the well casings, inadequate engineering, or any other number of reasons, a significant number of wells, once drilled and put into production or capped, leak a flow of natural gas from the annular space between the surface casing and the next casing wall. This interstitial flow of natural gas is known as the surface casing vent flow and must be vented, typically to the atmosphere. The surface casing vent flow is typically composed primarily of methane, but also includes ethane, propane, butane, and various other inert gasses. When the surface casing vent flow is vented to the atmosphere, a significant amount of methane, a greenhouse gas, is thus being emitted to the atmosphere.
The reduction of emissions of greenhouse gasses is part of an expanding and increasingly aggressive effort to combat climate change. To this effect, the Environmental Protection Agency (EPA) has set a goal of reducing methane emissions by 40-45% from 2012 levels by 2025 and other jurisdictions, such as Canada, are following the EPA's lead. This goal in reducing methane emissions by 2025 would potentially have a large effect on natural gas and oil drilling firms as methane is the predominant component of natural gas. One possible method of combating methane emissions is to react methane with oxygen to form carbon dioxide (and water). Although methane persists in the atmosphere for less time, methane is more than twenty-five times more powerful of a greenhouse gas than carbon dioxide in trapping heat on a common 100-year basis. Therefore, although this reaction forms carbon dioxide, which is also a greenhouse gas, it has a significant net benefit on climate change by reducing the overall effects of greenhouse gasses. If natural gas or oil flows received at a wellhead could be treated to convert endogenous methane to carbon dioxide prior to any emissions from the system reaching the atmospheric environment, then it could effectively and efficiently assist the natural gas and oil industry in complying with the EPA's methane emission goals.